1. Field of the Invention
The system of the present invention relates to golf courses. More particularly, the present invention relates to an improved bunker or trap utilized on a standard golf course, which facilitates drainage of water from the trap and improves the sand distribution in the trap.
2. General Background
The bunker designs in use today present three major maintenance problems to the maintenance crews at golf courses: (1) the sand that is on the high faces (areas that are the highest part of the bunker used to make it more visible to the golfer) of the bunkers will be washed off of the face during heavy rains and have to be pushed back up following the rain, which requires a great amount of hand labor from the golf course maintenance crew. (2) The sand that is used is most preferably of a light color or white, if possible. This gives the bunker the most preferred appearance. However, over a period of time this sand tends to get dirty or contaminated from the darker and smaller particles that are in the native soil below. This means that the sand must be replaced periodically at great expense to maintain the light color of the sand. (3) They are invariably very difficult areas of the course to drain since they are normally set down lower than any other part of the surrounding course. Two of these same problems occur in the draining of coal piles, and this design would therefore have benefits in other applications. Presently a soil cement is sprayed on the ground so that the coal stays above the native soils. The drain tile in a coal pile consist of gravel drains wrapped in geo-textile fabrics. With this design, the plastic liner could be placed on the ground surface and the drain line trenches dug down into the ground. Then the waffle drain could be used to replace the gravel and fabric drain presently used at a tremendous savings.
Normally the base grade of the bunker is cut into the shape of a bowl, with the sidewalls of the bunker sloped gradually down to the low point of the bunker. This design causes the water that is moving along the interface where the sand and base grade meet to pick up speed and start to erode the sand that is resting on the base grade. In the present design, the sidewalls are cut straight down and the gradual contour that was formed by the base grade is now formed by the contouring of the sand. This allows for the water to move straight down vertically and to move laterally across the bottom of the bunker floor at a rate much slower than if it was moving down a sidewall created at an angle less than perpendicular to the floor of the bunker.
The main attempts at stopping the sand from becoming contaminated have consisted of the use of a geo-textile fabric placed as a liner in between the sand surface and the base grade composed of native soil. This presents several problems, but the most persistent is that the fibers of the geo-textile become snagged by the piece of equipment used to maintain the bunker called a "sand pro". When this happens, the "sand pro" grabs the liner, pulls it out of position and requires that the liner be replaced. There are two reasons why these fabrics consistently snag: (1) the fact that one of the characteristics of the fibers used in the fabrics is that they have a lot of elongation or stretch. This allows them to pull when grabbed by the "sand pro"; and (2) because of present design techniques, the edges are placed at the part of the bunker that have the least amount of sand, which is the top edge of the bunker. In the past, the fabrics have been used because they allowed for the movement of the water through the fabric to the drain tile placed below. The generally accepted practice attempts to drain bunkers through the use of gravel bed and a 4 inch perforated pipe. These systems fail readily; the errodability of the sand used in the bunkers allows it to infiltrate the gravel bed and clog the drainage space. In addition, this gravel often works its way to the top and eventually is moved onto the green site that the bunker guards when an explosion shot is hit. This in turn causes damage to mowing equipment when used to cut the greens.
In the construction of golf courses, one of the most important items is the location and the construction of bunkers or traps which are positioned at strategic points along fairways, in order to present a greater challenge for a golfer during the golf game. At the present time, a trap is constructed in such a manner which would basically include the hollowing out in a type of saucer shape of a portion of ground, digging a series of trenches below the surface of the ground for incorporating a series of drainage lines for water being drained through the sand of the traps. When it is desirable to eliminate contact between the sand and the native soil, there would be positioned a layer of fluid permeable fabric such as geo-textile fabric along the floor of the trap to the very edges of the saucer shape foundation, and then there would be laid upon that a layer of sand which would serve as the trap media. The problems which are confronted with this standard construction of traps are several. One of the problems derives as a result of the flow of water into the bunker from the surrounding fairway so that as the water flows into the bunker it would essentially follow the slope of the "saucer" foundation, and from the peripheral edge of the bunker, down towards the lower portion of the trap, in the process the sand is eroded off of the top edge of the bunker, wherein there appears to be exposed a ridge of soil around the peripheral edge of the bunker, which would require hand labor to refurbish the sand in the trap in order to eliminate the erosion problem. Furthermore, as the sand is displaced from the edge of the trap, this would tend to expose geo-textile fabric laid to the peripheral edge of the saucer hollow, and during the "combing" of the sand in order to maintain the visual quality of the traps, exposed fabric may get snagged by the comb, and be pulled out of place, which would result in a very unsightly trap and a difficult problem to redistribute the fabric properly along the base of the trap.
These problems, as outlined, are addressed by the present invention, and the system of the present invention would tend to solve these problems as will be expressed following.